Motor problems such as clumsiness, toe-walking and altered gait are well documented in autism. But most studies have been limited to children or have included adults only as part of a broad age range.

“Studies haven’t focused on just adults,” says Cortney Armitano, a graduate student in Steven Morrison’s lab at Old Dominion University in Norfolk, Virginia, who presented the work.

The researchers looked at 20 young adults with autism between the ages of about 17 and 25, and 20 controls of about the same age range. They put these participants through a battery of standard tests of fine motor skills, balance and walking.

When it comes to simple tasks—such as tapping a finger rapidly against a hard surface or standing still without swaying—those with autism perform just as well as controls do.

But with activities that require more back-and-forth between the brain and the rest of the body, differences emerge.

Adults with autism have slower reaction times compared with controls, measured by how fast they can click a computer mouse in response to seeing a button light up. They also have a weaker grip.

Walk on by:

The researchers also documented altered gait in young adults with autism. These individuals take longer to take a step or a full stride, and have shorter strides than controls do. This means that they walk more slowly overall.

Looking at a wide range of motor skills simultaneously enabled the researchers to draw broader conclusions. Because tasks involving both the upper and lower limbs are affected, the results suggest slower overall processing of motor information rather than difficulty with a specific task.

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